SiBr_4及其不同离子态的电子结构研究——紫外光电子能谱(PES)和理论研究

Observation of Different Ionic State of SiBr_4——Photoelectron Spectroscopic and Theoretical Studies

本文详细报道了SiBr_4的紫外光电子能谱(PES)及该化合物不同离子态(X^2T_2,A^2T_1,B^2E,C^2T_2等)的电子结构和性质.实验测得对应基态离子态的绝热电离能I_a(X^2T_2←X^1A_1)=10.532eV,X^2T_2离子态的振动频率为(450±30)cm^(-1).结合理论计算对紫外光电子能谱进行了指认和分析,结果表明X^2T_2,A^1T_1两个离子态存在明显的自旋-轨道耦合作用,自旋-轨道耦合导致的分裂分别为:0.27eV和0.53eV.此外,不同计算方法比较显示外层格林函数方法计算得到电离能与实验吻合很好.

The Photoelectron Spectroscopy(PES) and different ionic state of SiBr4 were reported in this paper. The ionic states of SiBr4 + are X2 T2, A2 T1, B2E, C2 T2 respectively. The adiabatic ionization potential of the compound is Ia(X2T2←X1A1) = 10.532eV. A frequency of (450±30)cm-1 was observed in the PES band of X2 T2 ionic state. The assignment of the PE spectrum was performed with the help of the theoretical calculations and the band characters. Obvious Spin - Orbital Coupling split was observed in X2T2 and A2T1 states, and the splitting space are 0.27eV and 0.53eV. The comparison of different calculations shows that the Outer Valence Green' s Function (OVGF) method gives quite good results in ionization potentials calculations.